docs: def com_daltonmaag_check_ufolint(font):
    """Run ufolint on UFO source directory."""
    import subprocess
    ufolint_cmd = ["ufolint", font]
  
    try:
      subprocess.check_output(ufolint_cmd, stderr=subprocess.STDOUT)
    except subprocess.CalledProcessError as e:
      yield FAIL, ("ufolint failed the UFO source. Output follows :"
                   "\n\n{}\n").format(e.output.decode())
    except OSError:
      yield ERROR, "ufolint is not available!"
    else:
      yield PASS, "ufolint passed the UFO source."